1 files changed, 159 insertions, 0 deletions
diff --git a/src/effects/imagefilters/SkImageSource.cpp b/src/effects/imagefilters/SkImageSource.cpp
new file mode 100644
index 0000000000..960de37b33
--- /dev/null
+++ b/src/effects/imagefilters/SkImageSource.cpp
@@ -0,0 +1,159 @@
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkImageSource.h"
+
+#include "SkCanvas.h"
+#include "SkColorSpaceXformer.h"
+#include "SkImage.h"
+#include "SkReadBuffer.h"
+#include "SkSpecialImage.h"
+#include "SkSpecialSurface.h"
+#include "SkWriteBuffer.h"
+#include "SkString.h"
+
+sk_sp<SkImageFilter> SkImageSource::Make(sk_sp<SkImage> image) {
+    if (!image) {
+        return nullptr;
+    }
+
+    return sk_sp<SkImageFilter>(new SkImageSource(std::move(image)));
+}
+
+sk_sp<SkImageFilter> SkImageSource::Make(sk_sp<SkImage> image,
+                                         const SkRect& srcRect,
+                                         const SkRect& dstRect,
+                                         SkFilterQuality filterQuality) {
+    if (!image || srcRect.width() <= 0.0f || srcRect.height() <= 0.0f) {
+        return nullptr;
+    }
+
+    return sk_sp<SkImageFilter>(new SkImageSource(std::move(image),
+                                                  srcRect, dstRect,
+                                                  filterQuality));
+}
+
+SkImageSource::SkImageSource(sk_sp<SkImage> image)
+    : INHERITED(nullptr, 0, nullptr)
+    , fImage(std::move(image))
+    , fSrcRect(SkRect::MakeIWH(fImage->width(), fImage->height()))
+    , fDstRect(fSrcRect)
+    , fFilterQuality(kHigh_SkFilterQuality) {
+}
+
+SkImageSource::SkImageSource(sk_sp<SkImage> image,
+                             const SkRect& srcRect,
+                             const SkRect& dstRect,
+                             SkFilterQuality filterQuality)
+    : INHERITED(nullptr, 0, nullptr)
+    , fImage(std::move(image))
+    , fSrcRect(srcRect)
+    , fDstRect(dstRect)
+    , fFilterQuality(filterQuality) {
+}
+
+sk_sp<SkFlattenable> SkImageSource::CreateProc(SkReadBuffer& buffer) {
+    SkFilterQuality filterQuality = (SkFilterQuality)buffer.readInt();
+
+    SkRect src, dst;
+    buffer.readRect(&src);
+    buffer.readRect(&dst);
+
+    sk_sp<SkImage> image(buffer.readImage());
+    if (!image) {
+        return nullptr;
+    }
+
+    return SkImageSource::Make(std::move(image), src, dst, filterQuality);
+}
+
+void SkImageSource::flatten(SkWriteBuffer& buffer) const {
+    buffer.writeInt(fFilterQuality);
+    buffer.writeRect(fSrcRect);
+    buffer.writeRect(fDstRect);
+    buffer.writeImage(fImage.get());
+}
+
+sk_sp<SkSpecialImage> SkImageSource::onFilterImage(SkSpecialImage* source, const Context& ctx,
+                                                   SkIPoint* offset) const {
+    SkRect dstRect;
+    ctx.ctm().mapRect(&dstRect, fDstRect);
+
+    SkRect bounds = SkRect::MakeIWH(fImage->width(), fImage->height());
+    if (fSrcRect == bounds) {
+        int iLeft = dstRect.fLeft;
+        int iTop = dstRect.fTop;
+        // TODO: this seems to be a very noise-prone way to determine this (esp. the floating-point
+        // widths & heights).
+        if (dstRect.width() == bounds.width() && dstRect.height() == bounds.height() &&
+            iLeft == dstRect.fLeft && iTop == dstRect.fTop) {
+            // The dest is just an un-scaled integer translation of the entire image; return it
+            offset->fX = iLeft;
+            offset->fY = iTop;
+
+            return SkSpecialImage::MakeFromImage(SkIRect::MakeWH(fImage->width(), fImage->height()),
+                                                 fImage, ctx.outputProperties().colorSpace(),
+                                                 &source->props());
+        }
+    }
+
+    const SkIRect dstIRect = dstRect.roundOut();
+
+    sk_sp<SkSpecialSurface> surf(source->makeSurface(ctx.outputProperties(), dstIRect.size()));
+    if (!surf) {
+        return nullptr;
+    }
+
+    SkCanvas* canvas = surf->getCanvas();
+    SkASSERT(canvas);
+
+    // TODO: it seems like this clear shouldn't be necessary (see skbug.com/5075)
+    canvas->clear(0x0);
+
+    SkPaint paint;
+
+    // Subtract off the integer component of the translation (will be applied in offset, below).
+    dstRect.offset(-SkIntToScalar(dstIRect.fLeft), -SkIntToScalar(dstIRect.fTop));
+    paint.setBlendMode(SkBlendMode::kSrc);
+    // FIXME: this probably shouldn't be necessary, but drawImageRect asserts
+    // None filtering when it's translate-only
+    paint.setFilterQuality(
+        fSrcRect.width() == dstRect.width() && fSrcRect.height() == dstRect.height() ?
+               kNone_SkFilterQuality : fFilterQuality);
+    canvas->drawImageRect(fImage.get(), fSrcRect, dstRect, &paint,
+                          SkCanvas::kStrict_SrcRectConstraint);
+
+    offset->fX = dstIRect.fLeft;
+    offset->fY = dstIRect.fTop;
+    return surf->makeImageSnapshot();
+}
+
+sk_sp<SkImageFilter> SkImageSource::onMakeColorSpace(SkColorSpaceXformer* xformer) const {
+    SkASSERT(0 == this->countInputs());
+
+    auto image = xformer->apply(fImage.get());
+    if (image != fImage) {
+        return SkImageSource::Make(image, fSrcRect, fDstRect, fFilterQuality);
+    }
+    return this->refMe();
+}
+
+SkRect SkImageSource::computeFastBounds(const SkRect& src) const {
+    return fDstRect;
+}
+
+SkIRect SkImageSource::onFilterNodeBounds(const SkIRect& src, const SkMatrix& ctm,
+                                          MapDirection direction, const SkIRect* inputRect) const {
+    if (kReverse_MapDirection == direction) {
+        return SkImageFilter::onFilterNodeBounds(src, ctm, direction, inputRect);
+    }
+
+    SkRect dstRect = fDstRect;
+    ctm.mapRect(&dstRect);
+    return dstRect.roundOut();
+}
+